Is there a layout that fully matches CMYK and RGB?

Question

Design

The question is - there are many layouts like PANTONE ~ CMYK ~ RGB, but they indicate only an approximate color match. However, with a high degree of probability there are colors that are completely identical in "laboratory" conditions for CMYK and RGB, even if there are not many of them.
I do not take PANTONE into account, firstly, all printing, banners and film are printed in CMYK. Of course, it is good to use it for absolutely exact color matching, but this is true for large print runs and not all types of printing, rather an exception than a rule.
So, in short: are there at least 10 colors that absolutely exactly correspond to CMYK = RGB?
For example, mathematically obtained by analogy with "safe" web colors.

Answer 1

RGB and CMYK are not "layouts", but color models with their limitations associated with physics.
Based on, for example, the RGB color model, the sRGB color space is built, but sRGB is a rather crude attempt by hardware manufacturers to agree on a common color space. It is hardwired into operating systems, profiles for sRGB compatible hardware, distributed with drivers, and so on. But to get the "ultimate truth" you need to take a calibrator and build the color space of your monitor with preference and courtesans. The calibrator introduces an adjustment between what the video card + monitor wanted to display and what happened on the monitor as a result, this delta is called the color profile of the device.
Now we take a pair of printer + paper and return to your question. If we take awesome ilford paper and a 10-color canon pro9500, then we will get a print that, in terms of color reproduction, is indistinguishable from the image on the monitor to the untrained eye. And then we take Zewa toilet paper and refilled with expired ink from HP Ali MFP. The components of the ink are absorbed to varying degrees, but this can be compensated by the calibrator. We remove the profile of the car, add it to Photoshop and click "apply color profile". The picture becomes like on toilet paper, but we can compensate for this with curves to give the same expressiveness, if the client does not run after us with a colorimeter.
Why these 2 paragraphs? There is no RGB == CMYK, because the correspondence between color models is a purely mathematical thing, and the color space of your device is a thing that depends on dozens of parameters. At the minimum, manufacturers are trying to solve this problem ( https://ilford.com/printer-profiles-paper-settings/ paper profiles for the main printer models, but this is a premium segment). Therefore, even white and black colors cannot be included in your top ten. On the monitor, you can turn up the brightness, and the blackest one will turn gray, the white print depends on the whiteness of the paper.
About pantones. They appear in brand books precisely for the reasons listed above. When it comes to millions of copies, you can use not only process inks (CMYK), but also mixed inks (a bucket with such and such a pantone) for a logo. Beeline has a corporate color such and such a pantone of yellow and black. And you can color a million packages from 2 buckets, and not from 4 (also with jambs). An alternative to this is academic color spaces, but who will run around with a calibrator? Fan buy cheaper.

Answer 2

Theoretically, any CMYK color can be mapped to an RGB color (but not vice versa).

picture of color spaces